Chair construction and method therefore

ABSTRACT

In one embodiment, a chair includes a frame and a seat support coupled to the frame. The seat support is slidable relative to the frame from a disengaged position to an engaged position. A seat member is coupled to the seat support. The seat member is slidable relative to the seat support from a disengaged position to an engaged position. Methods of assembly are also provided.

This application claims the benefit of U.S. Provisional Application No.61/323,654, filed Apr. 13, 2010, the entire disclosure of which ishereby incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates generally to a chair, and in particular,to a chair construction, together with methods of use and assembly.

BACKGROUND

Chairs are often constructed using numerous fasteners, such as screws,rivets, nuts and bolts and the like. Assembly of the chair may be timeconsuming, requiring a technician to handle, position and manipulatemultiple fasteners, components and various tools. In some instances,expensive tooling fixtures may be required to hold and situate thecomponents relative to each other, such that the technician may thensecure the components together. Moreover, the technician must locate theproper size and type of fastener for each joint being assembled. Inaddition, the fasteners must be located and removed at the end of thelife cycle to allow for recycling of the components. Such actions may betime consuming and expensive.

SUMMARY

The present invention is defined by the following claims, and nothing inthis section should be considered to be a limitation on those claims.

In one aspect, one embodiment of a chair includes a frame configuredwith at least one of a tab or a slot. The frame also is configured withat least one of an opening and/or a protuberance. A seat support isconfigured with at least one of the other of the tab or the slot, andwith at least one of the other of the opening or the protuberance. Theseat support is moveable between a first position, wherein the tab isdisengaged from the slot and the protuberance is disengaged from theopening, and a second position, wherein the tab is engaged with the slotand the protuberance is received in the opening.

In another aspect, one embodiment of a method of assembling a chairincludes positioning the seat support relative to the frame and therebyaligning the tab with the slot and the protuberance with the opening.The method further includes moving the seat support and frame relativeto each other from a first position, wherein the tab is disengaged fromthe slot and the protuberance is disengaged from the opening, to asecond position, wherein the tab is engaged with the slot and theprotuberance is received in the opening.

In yet another aspect, one embodiment of a chair includes a frame and aseat support coupled to the frame. The seat support is slidable relativeto the frame in a horizontal direction from a disengaged position to anengaged position. A seat member is coupled to the seat support. The seatmember is slidable relative to the seat support in a horizontaldirection from a disengaged position to an engaged position.

In yet another aspect, one embodiment of a method of assembling a chairincludes sliding a seat support relative to a frame in a horizontaldirection from a disengaged position to an engaged position,immobilizing the seat support relative to the frame in the engagedposition, sliding a seat member relative to the seat support in ahorizontal direction from a disengaged position to an engaged position,and immobilizing the seat member relative to the seat support in theengaged position.

In yet another aspect, a backrest for a chair includes a first insertmember having at least one resilient tab member and a second insertmember having at least one catch member. A frame is sandwiched betweenthe first and second insert members. At least one opening is alignedwith the tab member and the catch member, with the tab member beingengaged with the catch member through the opening such that the firstand second inserts are coupled together with the frame sandwichedtherebetween.

The various embodiments of the chair and method for assembly providesignificant advantages over other seating structures. For example andwithout limitation, the chair may be assembled quickly and easily withminimal parts, and without the need for tooling fixtures. Specifically,the seat may be assembled and secured to the frame in a matter ofseconds without tools through the simple sliding engagement of the seatsupport to the frame and the seat member to the seat support. Indeed, inone embodiment, only a pair of fasteners are used to complete the entireassembly, thereby minimizing the risk of losing parts and requiring themanipulation of multiple tools. Likewise, the backrest and armrests (orplugs) may be quickly and easily assembled without separate fasteners.Moreover, in one embodiment, the backrest frame can be easily coveredand sandwiched by the insert members simply by engaging mating tab/catchmembers. Indeed, the entire chair may be assembled without any separatefasteners, and in an alternative embodiment with only a pair of separatefasteners. In addition, the chair may be easily disassembled at the endof its life cycle to facilitate the separation and recycling of thevarious components.

The foregoing paragraphs have been provided by way of generalintroduction, and are not intended to limit the scope of the followingclaims. The various preferred embodiments, together with furtheradvantages, will be best understood by reference to the followingdetailed description taken in conjunction with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective, exploded view of various alternative chairconstructions.

FIG. 2 is a perspective view of an upholstered backrest configuration.

FIG. 3 is a cross-sectional view of an upper portion of the backrestshown in FIG. 2.

FIG. 4 is a perspective view of a flexible backrest configurationincluding a peripheral frame.

FIG. 5 is a cross-sectional view of a connection between a frame and aflexible member.

FIG. 6 is a side view of one embodiment of the chair.

FIG. 7 is a partial, exploded, bottom perspective view of one embodimentof the frame, seat support and seat member.

FIG. 8 is a partial, exploded, top perspective view of the frame andseat support.

FIG. 9 is a partial, exploded, front perspective view of one embodimentof the frame, seat support and seat member.

FIG. 10A is a longitudinal cross-sectional view through one embodimentof the interface between the frame cross member and the seat support.

FIG. 10B is a longitudinal cross-sectional view through one embodimentof the tab and slot interface of the frame and seat support.

FIG. 11 is a lateral cross-sectional view through one embodiment of thetab, frame and seat support.

FIG. 12 is a partial exploded view showing one embodiment of theinterface between the seat support and seat member.

FIG. 13 is a partial view of one embodiment of the interface between theseat support and seat member.

FIG. 14A is a longitudinal cross-sectional view through one embodimentof the frame, seat support and seat member.

FIG. 14B shows enlarged portions of the longitudinal cross-sectionalview shown in FIG. 14A.

FIG. 15 is a partial, bottom perspective view of one embodiment of theinterface between the frame and backrest.

FIG. 16 is a cross-sectional view of one embodiment of the interfacebetween the frame, backrest and insert member.

FIG. 17A is a perspective view of on embodiment of a chair.

FIG. 17B is a perspective view of another embodiment of a chair.

FIG. 18 is a front view of one embodiment of a backrest member showingvarious bands.

FIG. 19 is a table with diagrams showing the various band properties forthe laterally extending bands shown in FIG. 18.

FIG. 20 is a table with diagrams showing the various band properties forthe diagonal/vertical bands shown in FIG. 18.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

It should be understood that the term “plurality,” as used herein, meanstwo or more. The term “longitudinal,” as used herein means of orrelating to length or the lengthwise direction, and in generalcorresponds to a direction running between a front and back or top tobottom, for example from a front of a seat to a back thereof, or from abottom of a backrest to the top thereof, and vice versa. The term“lateral,” as used herein, means situated on, directed toward or runningfrom side to side. The term “coupled” means connected to or engaged withwhether directly or indirectly, for example with an intervening member,and does not require the engagement to be fixed or permanent, althoughit may be fixed or permanent. The terms “first,” “second,” and so on, asused herein are not meant to be assigned to a particular component sodesignated, but rather are simply referring to such components in thenumerical order as addressed, meaning that a component designated as“first” may later be a “second” such component, depending on the orderin which it is referred. It should also be understood that designationof “first” and “second” does not necessarily mean that the twocomponents or values so designated are different, meaning for example afirst direction may be the same as a second direction, with each simplybeing applicable to different components.

Support Frame and Seat:

Referring to FIGS. 1 and 6-9, a seating structure is shown. The seatingstructure is configured as a chair, and includes a seat 2, a backrest 4and a base 6. In one embodiment, the base includes a frame 56 having apair of side members 8, each configured with a longitudinally extendingside support 10 and front and rear legs 14, 12. The side members areconnected with a cross member 16. Each of the side members has a post 58extending upwardly and rearwardly from the rear leg. The posts arecoupled to the backrest 4. Each of the side members 8 is formed from atubular structure, shown as having a circular cross section, although itshould be understood that other shapes and configurations would also besuitable. Glides 16 or casters are mounted to the bottom of the legs,with an insert portion 18 of the glide being disposed in the legs 14,12. In alternative embodiments, the frame may be configured as a sledbase, or be supported by a pedestal base.

The seat includes a seat support 20, configured as a seat pan in oneembodiment, and a seat member 22. The seat member 22 may be configuredas a shell 24 covered with a layer of foam 26 and upholstery 28. Inother embodiments, an upper surface of the shell may be exposed, or mayhave an opening, with a suspension material stretched across theopening. The seat support may be made of various materials, includingfor example and without limitation a glass filled nylon. The seat membershell may be made of polypropylene.

Referring to FIGS. 7-11, the seat support 20 includes a longitudinallyextending slot 30 formed along each side thereof, with the slot having amouth 32 at a forward end thereof, and a stop 34 formed at a rear endthereof. Each of the side frame members 8 includes an insert member 36,configured in one embodiment as a tab member extending laterallyinwardly. The tab members 36 may include a mounting flange 38, which iscoupled to the frame by welding, adhesives, fasteners (such as screws orrivets), and other suitable known attachment devices, and/orcombinations thereof. The tab has an opening 40 therethrough, configuredas a slot in one embodiment. The tab members 36 have a thickness andlength shaped to mate with one of the slots 30 formed in the side of theseat support 20. It should be understood that, in an alternativeembodiment, the slot may be formed in the side of the frame member, withthe tab extending laterally from the seat support, or some combinationthereof.

The seat support 20 further includes a plurality of insert members 42,configured as two protuberances or tabs, extending longitudinallyforwardly from a front portion 46 of the seat support. The frame crossmember 16 is configured with a corresponding plurality of openings 44shaped and positioned to receive the protuberances 42. It should beunderstood that the seat support may be configured with a plurality ofopenings, and the cross member configured with a plurality of tabs, orwith each configured with some combination thereof. It also should beunderstood that the cross member may be positioned adjacent a rearportion of the seat support, or some intermediate location.

In operation, the seat support 20 is positioned in a disengaged positionrelative to the frame, with the tabs 36 aligned and positioned adjacentthe mouths 32 of the slots 30. The seat support 20 is then slidforwardly in a horizontal direction with the tabs 36 sliding in theslots 30. It should be understood that the tab members 36, slots 30,protuberances 42 and openings 44 may be positioned and oriented suchthat the seat support is slid rearwardly relative to the frame from thedisengaged to the engaged position, for example when a cross member ispositioned at a rear portion of the frame.

It should be understood that movement in the horizontal direction has ahorizontal vector component, but may also include some movement in thevertical direction. Eventually, the seat support 20 is slid forwardlyuntil the protuberances 42 are aligned with the openings 44. The seatsupport 20 is then slid to an engaged position, with the protuberances42 inserted in the openings 44, and with the tabs 36 engaging the stopmember 34. A lock member 48, shown as a fastener, is then insertedthrough the seat support and through the opening in the tab member, soas to fix or immobilize the seat support relative to the frame. Thefastener may be a threaded fastener, such as a screw. However, it shouldbe understood that the lock member may be integrally formed on the seat,for example as a resilient tab member, or may be a pin that can insertedby hand, with a catch portion securing it with a snap fit. The loadplaced by the user on the seat support 20 is carried by and transferreddirectly to the frame 56 as shown in FIG. 11, with the bottom of theseat support bearing on the frame side support 10. The tab 36 interfacewith the seat support 20, including the lock member, prevents the seatfrom being lifted off of the frame, or from moving forwardly orrearwardly relative thereto.

The seat member 22, and in particular the shell 24, is configured with aplurality of catch members 50, shown in one embodiment as six. The catchmembers may be configured as loops in one embodiment. The seat supportis configured with a corresponding number of insert members 52, withsome of the insert members disposed in openings 54, and extendingforwardly from a front portion 46 of the seat support, and with some ofthe insert members 52 extending forwardly from a rear portion 56 of theseat support. It should be understood that the seat member may beconfigured with insert members, and the seat member configured withcatch members, or with both members configured with some combination ofeach.

In operation, the seat member 22 is positioned in a disengaged positionrelative to the seat support 20, with the insert members 52 aligned andpositioned adjacent the catch members 50. The seat member 22 is thenslid rearwardly in a horizontal direction with the insert members 52sliding into the catch members 50. Eventually, the seat member 22 isslid rearwardly until the seat member snaps into an engaged positionrelative to the seat support 20. In this configuration, one or both ofthe insert member and catch member may be provided with interfacingsnap-fit components, such as lips, or the front and rear portions of theseat member may snap into engagement with corresponding front and rearedges of the seat support as shown in FIG. 14. It should be understoodthat the insert members and catch members may be positioned and orientedsuch that the seat member is slid rearwardly relative to the seatsupport.

Backrest, Armrests and Plugs:

The backrest member 4 may be configured in many different arrangementsand materials. In all of the embodiments shown in FIGS. 1-5, thebackrest members 4 include a mounting portion 164 formed at the junctionof side and bottom edges. In one embodiment, the mounting portions 164are the only interface and support for the backrest to the frame 56. Ofcourse, other support structures may be used in other embodiments.

The mounting portion 164 has an opening 302, with a bottom 304 and top300 thereof. The frame posts 58 are inserted through a bottom of theopening. An insert member, which may be configured as either an armrests61 or a plug 64, each having an insert portion 57 is inserted through atop 300 of the opening and into one of the posts 58 to complete theassembly. The plug has a cap portion 69 that mates with and matches thecontour of the mounting portion. Alternatively, the insert member mayhave an opening, with the post being inserted into the insert member.

In one embodiment, the backrest member 6 and insert members 61, 64 areslid downwardly relative to the frame post 58, and the insert member isslid downwardly relative to the backrest member 6, from a disengagedposition to an engaged position. The upper portion 71 of each post isconfigured with a polygonal, or non-circular cross-sectional shape thatmates with a corresponding shape of the opening 302 formed through themounting portion 164, such that the mounting portions 164 and/or insertmember 61, 64 are non-rotatably fixed relative to the post member 58. Inone embodiment, there are two features that prevent rotation. The firstis the shape (e.g., hexagon) formed in the injection molded backrestmember. That shape will mate with and provide a tight fit to the arm,which has a corresponding shape to prevent looseness of the arm. Thesecond is the hexagon shape of the metal frame. This is a looser fit.When the arms are loaded heavily, the arms and back will deform and thearm load will be transferred to the hex tube 71 in the base. A lowerportion of the post 58 is configured as a round tube 73, which is sizedand shaped to match the other portions of the frame. The upper portion,which has an outermost cross-sectional periphery shaped to be receivedin the tube 73, may be welded, bonded or otherwise affixed to the lowerportion. In one embodiment, shown in FIG. 17A, a sled base includes ahex tube 71 that is plug welded to the outer tube 81, with joint thencovered by the cross tube 83. In the embodiment shown in FIG. 17B, thehex tube 71 is bent along with the outer tube 73 that prevents relativerotation therebetween, and may not need to be welded, bonded, orotherwise affixed to the lower portion, but may be in various suitableembodiments.

The mounting portion 164 of the backrest 4 has a cavity 308 formed on abottom thereof. A lock member 310, including a retainer pin 312, iscoupled to the mounting portion, with a grippable portion 320 exposedand accessible to the user in the cavity. In one embodiment, the lockmember is formed from a resilient wire, with an upstanding leg 314inserted in and engaging the mounting portion, and with first, second,third and fourth loops 316, 318, 320, 322, terminating in a horizontallyextending leg 334. The fourth loop 322 forms a slot 324, which can beengaged by a tool, such as a screw driver, to bias the leg 334 to adisengaged position. The post, including the lower portion 73 and upperportion 71, and insert portion 57 each have openings 330, 332, 336formed therein, which when aligned in an assembled position, are engagedby the leg 334 of the retainer pin 312 in an engaged position so as tolock the insert member 61, 64 and backrest 4 to the post 58. Todisassemble either or both of the backrest 4 and insert member (plug orarm) 61, 64, for example to replace a plug with an armrest or viceversa, the retainer member 312 is biased to a disengaged position, withthe insert member and backrest then being removed and/or replaced withanother or the same insert member and/or backrest member.

Referring to FIG. 1, in one embodiment, the backrest member 160 issimply made of a rigid plastic material, for example and withoutlimitation glass-filled nylon, but with a shape similar to that shown inthe other embodiments, namely a curved lower edge 194 longer than anupper edge 196, with a middle portion of the curved edge positionedbelow ends thereof, forwardly and downwardly extending side edges 198, aforwardly facing concave shape taken along a vertical centerline, and aforwardly facing convex shape extending laterally in the lumbar region.The backrest member 160 may have openings 162 formed therethrough toprovide air circulation and improved aesthetics.

In another embodiment, shown in FIGS. 1-3, the backrest member includesa shell 170 coupled to front and rear inserts 172, 174. A layer of foam176 covers the front, with fabric 178, 180 then covering the foam andthe rear insert. A peripheral edge 182 of the shell remains exposed. Theinserts each include a plurality of resilient tab members 184, 186, orcatch members, that extend through openings 188 formed in the shell 170.The resilient tab members (catch members) 184, 186 are engaged with asnap fit to complete the assembly, sandwiching the shell 170 between theinserts. In one embodiment, the frame is provided with flange membersthat are engaged by and locate the insert members, such that the insertmembers and frame are not moveable relative to each other laterally orlongitudinally. In one embodiment, the tab/catch members are the onlycomponents securing the insert members to the frame sandwichedtherebetween. The front fabric layer 178 covers the foam layer 176 andhas an edge portion 190 that extends into a spaced formed between theshell 170 and the front insert 172. Likewise, the rear fabric layer 180has an edge portion 192 that extends into a spaced formed between therear insert 174 and the shell 170. In one embodiment, the fabric may bestapled to the inserts, while in other embodiments, they may be glued.Again, the backrest assembly has a shape similar to that shown in theother embodiments, but with the mounting portion 200 at the junction ofthe side and bottom edges being the sole mounting portion, such that thecurved support and upper supports may be eliminated. The mountingportion 163 engages a post 58, or other like support structure.

In yet another embodiment, shown in FIGS. 1 and 4-5, a peripheral frame202 is provided that forms a central opening 204, and which has achannel 206 formed around a forwardly facing periphery thereof. Aflexible member 208, is provided with a peripheral edge portion 210. Aretainer 212 includes an edge portion 213 that engages the edge portion210 of the flexible member and holds the flexible member in and againstthe frame channel 206. Fasteners 214, such as screws, tabs, snap-fit,etc. couple the retainer 212 to the frame 202, with the flexible member208 disposed and trapped therebetween. Again, the backrest assembly hasa shape similar to that shown in the other embodiments, but with themounting portion 164 at the junction of the side and bottom edges beingthe sole mounting portion, such that the curved support and uppersupports may be eliminated. The mounting portion engages a post, orother like support structure.

In the embodiment shown in FIGS. 1 and 4-5, the backrest member is madeof a flexible elastomeric material, for example and without limitationan elastomeric copolyester, e.g., Amitel, or an elastomeric urethane.The backrest member has a thickness between about 2.5 mm and 4.5 mm. Themember can be configured with a plurality of openings formedtherethrough, or thought of as a series of intersecting straps or bandsthat extend laterally (horizontally) and longitudinally (diagonally andvertically). The horizontal and vertical straps have different typicalcross-sections. For example, the horizontal straps have a triangularcross section with the “top point” of the triangle facing the rear ofthe chair. The vertical straps are oval.

Referring to FIGS. 18-20, the height and thickness of a strand or bandof material may vary, for example inversely such that the strand may beappear to be thinner at the laterally aspects of the backrest, yet haveapproximately the same cross-section area. In various embodiments, anyof the laterally or vertically/diagonally extending bands may vary incross sectional area to create zones of higher stiffness. Referring toFIGS. 18 and 19, lateral bands H1-H36 are sequentially called out fromthe upper, outer corners to the bottom of the backrest, with variouscross-sectional shapes and areas shown. Likewise, referring to FIGS. 18and 20, diagonal/vertical bands V0-V11 are sequentially called out froman outermost lateral position (V1) moving inwardly, with a pair of V11strands converging to form a single band along a centerline position atthe bottom portion of the backrest member. Additional upper diagonalbands also converge at intersecting laterally bands as shown. The bandor strand may be thickened in areas in which increased support(stiffness) is desired. For example, supporting the user at the core(near the centerline of the back) may be desirable, thus ‘islands’ ofthicker strands or bands may be utilized to give increased support inthe sacral, lumbar, and thoracic areas along the centerline of thebackrest. This will increase the bending stiffness in that area. Invarious embodiments, the backrest member may be molded with athree-dimensional shape even when free of any tension or constraints, ormay be molded or formed as a flat member, with the three-dimensionalshape being introduced by way of the tension and connections to thesupport structure.

The elastomeric material may be oriented, for example by compression orstretching, to provide the backrest member with different load bearingcharacteristics in different directions. In other embodiments, thematerial is not oriented. Various oriented elastomeric materials andmethods of making components from such materials are disclosed in U.S.Publication 2006, 0267258A1, published Nov. 30, 2006 and U.S.Publication 2006/0286359 A1, published Dec. 21, 2006, the entiredisclosures of which are hereby incorporated herein by reference. Thebackrest member may alternatively be made of a fabric, or of anelastomeric membrane, for example as a woven membrane as disclosed inU.S. Pat. No. 6,059,368, the entire disclosure of which is herebyincorporated herein by reference.

In one embodiment, the backrest member has an upper portion with anupper edge 86, opposite side edges 90 and a lower portion with a loweredge 88. The upper edge 86 is shorter than the lower edge 88. The loweredge 88 has end portions 92 that are positioned forwardly of the upperedge 86, with the side edges 90 extending downwardly and forwardly fromthe upper edge 86 to the lower edge 88. The lower edge 88 has aforwardly facing concave shape, which mates with the curved bottomsupport 64 on the frame. A middle portion 94 of the lower edge ispositioned reardwardly of the upper edge 86, and beneath an uppersupport surface of the seat member 22 and behind a rear portion of theseat 2. In this way, and due to the curvature, length and positioning ofthe lower edge 86, the lower edge has end portions 92 positioned infront of the upper edge 86 and a middle portion 94 positioned rearwardlyof the upper edge 86 when the backrest is in a normal, upright position.

Further aspects of the backrest are disclosed in a U.S. ProvisionalApplication (Attorney Docket No. 3591-1816) entitled SEATING STRUCTUREWITH A CONTOURED FLEXIBLE BACKREST and filed the same day as the presentapplication, with the entire disclosure thereof hereby beingincorporated herein in its entirety.

Although the present invention has been described with reference topreferred embodiments, those skilled in the art will recognize thatchanges may be made in form and detail without departing from the spiritand scope of the invention. As such, it is intended that the foregoingdetailed description be regarded as illustrative rather than limitingand that it is the appended claims, including all equivalents thereof,which are intended to define the scope of the invention.

1. A chair comprising: a frame comprising one of a tab extending in afirst direction or a slot extending in a second direction perpendicularto said first direction and one of an opening or a protuberance formedthereon, said opening facing said second direction and said protuberanceextending in said second direction; and a seat support having the otherof said tab or said slot and the other of said opening or saidprotuberance, wherein said seat support is moveable in said seconddirection between a first position, wherein said tab is disengaged fromsaid slot and said protuberance is disengaged from said opening, and asecond position, wherein said tab is engaged with said slot and saidprotuberance is received in said opening.
 2. The chair of claim 1wherein said seat support is further moveable to a third positionbetween said first and second positions, wherein said tab is engagedwith said slot and said protuberance is disengaged with said opening. 3.The chair of claim 1 wherein said seat support is locked to said framewhen said seat support is in said second position.
 4. The chair of claim3 further comprising a lock member inserted through said tab andengaging the other of said frame or said seat support defining saidslot.
 5. The chair of claim 1 wherein said frame comprises a pair oflaterally spaced and longitudinally extending side frame members coupledto a laterally extending cross member, wherein said tab is connected toand extends laterally inwardly from one of said side frame members andsaid seat support comprises said slot, and wherein said cross membercomprises said one of said opening or said protuberance.
 6. The chair ofclaim 5 wherein said cross member comprises a plurality of said openingsand said seat support comprises a plurality of said protuberances. 7.The chair of claim 1 further comprising a seat member coupled to saidseat support.
 8. The chair of claim 7 wherein one of said seat memberand said seat support comprises an insert member, and the other of saidseat member and said seat support comprises a catch member, wherein saidseat member is moveable relative to said seat support from a firstposition, wherein said insert member is disengaged from said catchmember, to a second position, wherein said insert member is engaged withsaid catch member.
 9. The chair of claim 8 wherein said frame comprisesan upwardly extending post, and further comprising a backrest having amounting portion with an opening formed therein, wherein said post isdisposed in a bottom of said opening formed in said mounting portion,and further comprising an insert member disposed through a top of saidopening formed in said mounting portion, wherein said insert member isengaged with said post, and further comprising a lock member disposedthrough said mounting portion, said post and said insert member.
 10. Thechair of claim 9 wherein said insert member comprises one of an armrestor a plug.
 11. The chair of claim 9 wherein said lock member comprises areleasable retainer pin moveably mounted to said backrest, wherein saidretainer pin is accessible through an opening formed in the bottom ofsaid mounting portion, and is moveable between a lock position, whereinsaid retainer pin is engaged with said post and said insert member, andan unlocked position, wherein said retainer pin member is disengagedwith said post and said insert member.
 12. A method of assembling achair comprising: providing a frame comprising one of a tab or a slotand a cross member comprising one of an opening or a protuberance formedthereon; providing a seat support having the other of said tab or saidslot and the other of said opening or said protuberance; positioningsaid seat support relative to said frame and thereby aligning said tabwith said slot and said protuberance with said opening; and moving saidseat support and said frame relative to each other from a firstposition, wherein said tab is disengaged from said slot and saidprotuberance is disengaged from said opening, to a second position,wherein said tab is engaged with said slot and said protuberance isreceived in said opening.
 13. The method of claim 12 wherein said movingsaid seat support and said frame relative to each other from said firstposition to said second position comprises moving said seat support andsaid frame relative to each other from said first position to a thirdposition, wherein said tab is engaged with said slot and saidprotuberance is disengaged with said opening, and then moving said seatsupport and said frame relative to each other from said third positionto said second position.
 14. The method of claim 12 further comprisinglocking said seat support to said frame when said seat support is insaid second position.
 15. The method of claim 14 wherein locking saidseat support to said frame comprises inserting a lock member throughsaid tab and engaging the other of said frame or said seat supportdefining said slot.
 16. The method of claim 12 wherein said framecomprises a longitudinally extending side frame member coupled to saidcross member, wherein said tab is connected to and extends laterallyinwardly from said side frame member.
 17. The method of claim 12 furthercomprising coupling a seat member to said seat support.
 18. The methodof claim 17 wherein one of said seat member and said seat supportcomprises an insert member, and the other of said seat member and saidseat support comprises a catch member, and wherein said coupling saidseat member to said seat support comprises moving said seat memberrelative to said seat support from a first position, wherein said insertmember is disengaged from said catch member, to a second position,wherein said insert member is engaged with said catch member.
 19. Themethod of claim 18 wherein said frame comprises an upwardly extendingpost, and further comprising providing a backrest having a mountingportion with an opening formed therein, disposing said post in a bottomof said opening formed in said mounting portion, disposing an insertmember through a top of said opening formed in said mounting portion,engaging said insert member with said post, and locking said mountingportion and said insert member to said post.
 20. The method of claim 19wherein said locking said mounting portion and said insert member tosaid post comprises moving a lock member coupled to said backrest from aunlocked position, wherein said lock member is disengaged from said postand said insert member, to a locked position, wherein said lock memberis engaged with said post and said insert member.
 21. A method ofassembling a chair comprising: sliding a seat support relative to aframe in a horizontal direction from a disengaged position to an engagedposition; immobilizing said seat support relative to said frame in saidengaged position; sliding a seat member relative to said seat support ina horizontal direction from a disengaged position to an engagedposition; and immobilizing said seat member relative to said seatsupport in said engaged position.
 22. The method of claim 21 furthercomprising sliding a backrest relative to a frame in a downwarddirection from a disengaged position to an engaged position, andimmobilizing said backrest relative to said frame in said engagedposition.
 23. The method of claim 22 further comprising sliding aninsert member relative to said backrest and said frame from a disengagedposition to an engaged position, and immobilizing said insert member.24. The method of claim 23 wherein said immobilizing said backrest andsaid immobilizing said insert member are performed simultaneously.
 25. Achair comprising: a frame; a seat support coupled to said frame, whereinsaid seat support is slidable relative to said frame in a horizontaldirection from a disengaged position to an engaged position; and a seatmember coupled to said seat support, wherein said seat member isslidable relative to said seat support in a horizontal direction from adisengaged position to an engaged position.
 26. The chair of claim 25further comprising a backrest coupled to said frame, wherein saidbackrest is slidable relative to said frame in a downward direction froma disengaged position to an engaged position.
 27. The chair of claim 26further comprising an insert member coupled to said frame, wherein saidinsert member is slidable through an opening formed in said backrestrelative to said frame in a downward direction from a disengagedposition to an engaged position. 28-33. (canceled)